Mach Speed Converter

Enter Mach multiple, or speed:

From units ...

To

Result:

Decimal

Scientific

Enter a Mach Multiple, or a Speed

Enter a Mach multiple (i.e. a speed of sound multiple), or a speed value, that you want to convert.
For example, enter 1 (for Mach-1, the speed of sound), or 0.5 (for Mach-0.5, half the speed of sound),
or 712 (for the speed of sound in mph at 18,000 feet of altitude), and so on.
TIP:
This converter is for sound in air, and is calibrated for the International Standard Atmosphere (ISA),
but does include some conversions for speed of sound in metal and water.
Input Format
Your entry should be in one of these formats:
Integer:1Decimal:+0.998Scientific Notation:2.7E-2Formula:(1+(6.5/1.8e-2))/(2.7*5e2)Fraction:3/8Calculator Memory:
You can use the results from previous conversions or calculations, which you may have saved
in the Calculator Memory.
First click inside the Mach or speed input field to select it, then click the Recall button on one of the Memories.
The memory contents is loaded to the input field.
See the Calculator Memory for more details.
Maximum Input Length: 200 characters

From and To Mach and Speed Units

From Menu
In this menu, choose the altitude at which your sound is occurring, or the speed units
of the value you entered in the input field. For example one of these.
mach (3000 feet ISA)mach (18000 feet ISA)mach (30000 feet ISA)kilometers per hourmiles per hourfeet per secondTo Menu
In this menu, choose the speed units you want to convert to,
or choose an altitude for the Mach multiple of your result.
For example, choose one of these.
meters per secondmiles per hourkilometers per hourmach (60000 feet ISA)mach (15000 feet ISA)mach (6000 feet ISA)TIP:
Drag your mouse pointer in the To or From menu to change units. Release the mouse button to perform a new conversion.
TIP:
Select units in the To or From menu. Press the Up and Down arrow keys on the keyboard to change units and do a new conversion.

The Result – Two Items

The first item is the Mach multiple, or the speed value, that you entered in the input field,
shown here again as a number, with the units that are selected in the From menu.
The second item is the conversion result, with units of either:
a) Mach multiple at altitude selected in To menu, or
b) Speed with the units selected in To menu
Calculator Memory
You can save the result of your conversion in the Calculator Memory,
then use your saved results later as input for other converters and calculators
anywhere on the website.
See the Calculator Memory for more details.
TIP:Precision of the converter is 12 significant digits, from left to right. Digits after the 12 left-most digits, are not significant.
Numeric Range of the converter is:
+1.797e+308 to -1.797e+308+1.000e-311 to -1.000e-311TIP:Error messages, if any, are displayed here.

The Control Buttons

The Mach to speed converter has three control buttons.
Decimal and Scientific buttons let you choose the output format, as one of these two:
Decimal:-9999.1Scientific Notation:-9.9991e3Decimal Button
In this mode the converter will output in Decimal format whenever possible.

However, the converter will automatically output in Scientific Notation
when the results cannot be shown properly in Decimal format.
Scientific Button
In this mode the converter will always output in Scientific Notation.
Convert Button
Convert the Mach multiple, or the speed, that you entered above, by using any of these methods:

Click the Convert button

Select a different unit in the From menu

Select a different unit in the To menu

Click the Decimal or the Scientific button

Press Enter or Return on keyboard

TIP:Scientific Notation is better for visualizing and working with big and small numbers, compared to decimal format.